C++ const_iterator::type方法代码示例

void QgsVectorDataProvider::fillMinMaxCache()
{
  if ( !mCacheMinMaxDirty )
    return;

  const QgsFieldMap& flds = fields();
  for ( QgsFieldMap::const_iterator it = flds.begin(); it != flds.end(); ++it )
  {
    if ( it->type() == QVariant::Int )
    {
      mCacheMinValues[it.key()] = QVariant( INT_MAX );
      mCacheMaxValues[it.key()] = QVariant( INT_MIN );
    }
    else if ( it->type() == QVariant::Double )
    {
      mCacheMinValues[it.key()] = QVariant( DBL_MAX );
      mCacheMaxValues[it.key()] = QVariant( -DBL_MAX );
    }
    else
    {
      mCacheMinValues[it.key()] = QVariant();
      mCacheMaxValues[it.key()] = QVariant();
    }
  }

  QgsFeature f;
  QgsAttributeList keys = mCacheMinValues.keys();
  select( keys, QgsRectangle(), false );

  while ( nextFeature( f ) )
  {
    QgsAttributeMap attrMap = f.attributeMap();
    for ( QgsAttributeList::const_iterator it = keys.begin(); it != keys.end(); ++it )
    {
      const QVariant& varValue = attrMap[*it];

      if ( flds[*it].type() == QVariant::Int )
      {
        int value = varValue.toInt();
        if ( value < mCacheMinValues[*it].toInt() )
          mCacheMinValues[*it] = value;
        if ( value > mCacheMaxValues[*it].toInt() )
          mCacheMaxValues[*it] = value;
      }
      else if ( flds[*it].type() == QVariant::Double )
      {
        double value = varValue.toDouble();
        if ( value < mCacheMinValues[*it].toDouble() )
          mCacheMinValues[*it] = value;
        if ( value > mCacheMaxValues[*it].toDouble() )
          mCacheMaxValues[*it] = value;
      }
      else
      {
        QString value = varValue.toString();
        if ( mCacheMinValues[*it].isNull() || value < mCacheMinValues[*it].toString() )
        {
          mCacheMinValues[*it] = value;
        }
        if ( mCacheMaxValues[*it].isNull() || value > mCacheMaxValues[*it].toString() )
        {
          mCacheMaxValues[*it] = value;
        }
      }
    }
  }

  mCacheMinMaxDirty = false;
}

void QgsMergeAttributesDialog::createTableWidgetContents()
{
  //get information about attributes from vector layer
  if ( !mVectorLayer )
  {
    return;
  }

  //combo box row, attributes titles, feature values and current merge results
  mTableWidget->setRowCount( mFeatureList.size() + 2 );

  //create combo boxes and insert attribute names
  const QgsFieldMap& fieldMap = mVectorLayer->pendingFields();

  int col = 0;
  for ( QgsFieldMap::const_iterator fieldIt = fieldMap.constBegin();
        fieldIt != fieldMap.constEnd();
        ++fieldIt )
  {
    if ( mVectorLayer->editType( fieldIt.key() ) == QgsVectorLayer::Hidden ||
         mVectorLayer->editType( fieldIt.key() ) == QgsVectorLayer::Immutable )
      continue;

    mTableWidget->setColumnCount( col + 1 );

    mTableWidget->setCellWidget( 0, col, createMergeComboBox( fieldIt->type() ) );

    QTableWidgetItem *item = new QTableWidgetItem( fieldIt.value().name() );
    item->setData( Qt::UserRole, fieldIt.key() );
    mTableWidget->setHorizontalHeaderItem( col++, item );
  }

  //insert the attribute values
  QStringList verticalHeaderLabels; //the id column is in the
  verticalHeaderLabels << tr( "Id" );

  for ( int i = 0; i < mFeatureList.size(); ++i )
  {
    verticalHeaderLabels << QString::number( mFeatureList[i].id() );

    const QgsAttributeMap &attrs = mFeatureList[i].attributeMap();

    for ( int j = 0; j < mTableWidget->columnCount(); j++ )
    {
      int idx = mTableWidget->horizontalHeaderItem( j )->data( Qt::UserRole ).toInt();

      QTableWidgetItem* attributeValItem = new QTableWidgetItem( attrs[idx].toString() );
      attributeValItem->setFlags( Qt::ItemIsEnabled | Qt::ItemIsSelectable );
      mTableWidget->setItem( i + 1, j, attributeValItem );
      mTableWidget->setCellWidget( i + 1, j, QgsAttributeEditor::createAttributeEditor( mTableWidget, NULL, mVectorLayer, idx, attrs[idx] ) );
    }
  }

  //merge
  verticalHeaderLabels << tr( "Merge" );
  mTableWidget->setVerticalHeaderLabels( verticalHeaderLabels );

  //insert currently merged values
  for ( int i = 0; i < mTableWidget->columnCount(); ++i )
  {
    refreshMergedValue( i );
  }
}